Originally for Unix platforms in 1987, Sybase Corporation's primary relational database management system product was initially marketed under the name Sybase SQL Server.[1][2] In 1988, SQL Server for OS/2 was co-developed for the PC by Sybase, Microsoft, and Ashton-Tate.[3] Ashton-Tate divested its interest and Microsoft became the lead partner after porting SQL Server to Windows NT. Microsoft and Sybase sold and supported the product through version 4.2.1.
Sybase released SQL Server 4.8 in 1992. This release included internationalization and localization and support for symmetric multiprocessing systems.